Hi Farhan,
Sorry for the delay in getting back to you.
It is possible to insert the image into the PDF document
from the Image element using WriteableBitmap. But currently we do not have
support to convert the Rich text formats to PDF document. We will let you know
once the feature has been implemented.
Please find the sample available in the link below,
InsertImageInPDF.zip
Please let us know if you have any questions.
Regards,
George